CVE-2024-56523 is a critical vulnerability affecting Radware Cloud Web Application Firewall (WAF) versions prior to May 7, 2025. The flaw allows remote attackers to bypass firewall filtering mechanisms by exploiting the way the WAF processes HTTP GET requests containing random data in the request body. Normally, HTTP GET requests do not include a body, and many WAFs do not expect or properly parse such data. In this case, the Radware Cloud WAF fails to correctly handle or validate the presence of arbitrary data in the body of GET requests, enabling attackers to circumvent security rules and filters designed to block malicious traffic. This bypass can lead to unauthorized access or the delivery of malicious payloads to protected web applications. The vulnerability is classified under CWE-444 (Inconsistent Interpretation of HTTP Requests), indicating that the WAF's inconsistent parsing of HTTP requests leads to security control failures. The CVSS v3.1 base score is 9.1, reflecting a critical severity due to the vulnerability's remote exploitability without authentication or user interaction, and its potential to compromise confidentiality and integrity of protected systems. Although no known exploits are currently reported in the wild, the high severity and straightforward exploitation vector make this a significant threat to organizations relying on Radware Cloud WAF for web application security.

For European organizations, this vulnerability poses a serious risk to the security of web applications protected by Radware Cloud WAF. Successful exploitation could allow attackers to bypass critical security controls, potentially leading to unauthorized data access, data exfiltration, or manipulation of web application content. This undermines confidentiality and integrity, particularly for organizations handling sensitive personal data subject to GDPR compliance. The absence of disruption to availability means attacks may go unnoticed while data breaches occur. Sectors such as finance, healthcare, government, and e-commerce in Europe, which often deploy WAFs to protect sensitive customer and operational data, are especially vulnerable. The vulnerability could facilitate advanced persistent threats (APTs) or opportunistic attacks, increasing the risk of regulatory penalties, reputational damage, and financial loss. Given the critical nature of the flaw and the widespread use of WAFs in European enterprises, the impact is potentially broad and severe.

European organizations using Radware Cloud WAF should immediately verify their deployment versions and apply any available patches or updates released after May 7, 2025, that address this vulnerability. In the absence of patches, organizations should implement compensating controls such as: 1) Enforcing strict validation and normalization of HTTP requests at upstream proxies or load balancers to reject GET requests with unexpected bodies; 2) Monitoring and logging anomalous HTTP GET requests containing bodies for early detection of exploitation attempts; 3) Employing additional security layers such as runtime application self-protection (RASP) or enhanced intrusion detection systems (IDS) to detect suspicious traffic patterns; 4) Conducting thorough security assessments and penetration tests focusing on HTTP request handling; 5) Reviewing and tightening WAF rulesets to minimize reliance on vulnerable parsing logic; and 6) Coordinating with Radware support for guidance and timely updates. Organizations should also update incident response plans to include detection and mitigation steps for this specific bypass technique.